Hello Juno! Welcome to the HorseForum! Don't think I've chatted with you yet!
Congrats on your new filly! Exciting stuff!
First thing I would suggest doing is working with those feet. Good feet are very important!
When we get a horse, younger or older, that won't let us handle their feet we always do the same thing, unless of course it's desperate that they need their feet done right now. First of all groom, groom, groom and make sure you work your way down her legs as far as you can until she starts to panic. Do this until you can brush her legs down all the way. Be sure to use a soft bistle brush as they have very sensitive legs. Once you can brush her legs right down to the hoofs then we start picking them up. We always use a soft cotton rope so that when they fight they don't win. Just loop it around their leg, make sure there is no clips, snaps, or knots that can injury the leg. Do this for a couple of days, on both back and front legs and in no time at all she will let you pick up all feet willing!
As for training here is my advice.
Lots of lunging, make sure she knows all the voice commands, walk, trot, whoa, easy. This makes your job soooo much easier. Trust me, I've started horses that don't know and horse that do know. The horses that already know are so much easier and more enjoyable to ride. I would not to any hard riding until she is three. I would say that it's okay to sit on her back and take a couple of steps but not any hard riding. Aside from lunging, do tons of sacking out and side rein work. Be sure that your hosre knows what you want when you pull back, or ask her to turn BEFORE you get on her back.
And most importantly, spend tons of time bonding. Groom her, hug her, love her. Just be with her. Let that little mare learn to trust you and then it'll be much easier to find trust in her as well. She won't give you her trust until she has yours.
Sorry about the novel..lol!
Would love to see some pictures of her!